Reactive oxygen species (ROS) are known to contribute as pathogenic factors to the development of chronic progressive diseases at various stages. ROS are also involved in a variety of different cellular processes ranging from apoptosis and necrosis to cell proliferation and carcinogenesis. ROS are well recognized for playing a dual role as both deleterious and beneficial species. They are also capable of inducing DNA damage that eventually may contribute to cell transformation and tumor initiation and are also associated with tumor promotion and progression. ROS also act as primary or secondary messengers to promote cell growth or death. In Phase I research, we will develop a microplate-based zebrafish whole animal assay to assess drug-induced oxidative stress. PUBLIC HEALTH RELEVANCE: Molecular players comprise both reactive oxygen (ROS) and reactive nitrogen species (RNS), which are known to contribute as pathogenic factors to the development of chronic progressive diseases at various stages.